1. Field of Invention
The present invention relates to a padlock and, more particularly, to a padlock including a shackle locked by key-operable locking mechanism at an end and locked by combination locking mechanism at another end so that the padlock can be unlocked by using a key or dialing the combination locking mechanism to an unlocking number.
2. Related Prior Art
To prevent belongings from missing, travelers usually lock their trunks, suitcases, briefcases, bags or the like. A combination lock is the most common lock installed in a trunk because it takes little space. Each traveler sets up an unlocking number for the combination lock. Thereby, others cannot unlock his trunk without knowing the unlocking number. However, terrorists may use trunks to deliver explosives. In airports, security personnel may have to check travelers' trunks without their presence. In some countries, travelers are required not to lock their trunks. The travelers may lose their belongings if leaving their trunks unlocked. If the travelers lock their trunks, the security personnel are authorized to break the trunks for security check. There is a dilemma between the travelers' rights and the flight safety. Therefore, there is a need for padlocks that can protect the travelers' belongings and allow the security personnel to unlock them.